/*-
 * Copyright (c) 2009 Jonathan Anderson
 * All rights reserved.
 *
 * WARNING: THIS IS EXPERIMENTAL SECURITY SOFTWARE THAT MUST NOT BE RELIED
 * ON IN PRODUCTION SYSTEMS.  IT WILL BREAK YOUR SOFTWARE IN NEW AND
 * UNEXPECTED WAYS.
 * 
 * This software was developed at the University of Cambridge Computer
 * Laboratory with support from a grant from Google, Inc. 
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 */

#include <sys/capability.h>
#include <sys/socket.h>
#include <sys/un.h>

#include <libuserangel.h>

#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <sysexits.h>
#include <unistd.h>

#include <libuserangel.h>

#include "Exception.h"
#include "policy.h"

using namespace userAngel;


int default_policy(enum ua_request_t req, userAngel::UserAngel::Datum d)
{
	switch(req)
	{
		case UA_NO_OP:	return 1;

		case UA_CACHE_FD:
		case UA_RETRIEVE_FD:
			/*
			 * allow all FD caches and retrievals, as they only work if
			 * you already have a capability (FD or crypto token) to
			 * access the file
			 */
			return 1;

		case UA_CHECK_ACCESS:
		case UA_STAT:
		case UA_OPEN_PATH:
			{
				QString path = d.toString();

				// no tricky paths allowed
				if(path.contains("..")) return 0;


				// whitelisted paths
				const char* paths[] = { "/cap/", NULL };

				for(int i = 0; paths[i] != NULL; i++)
					if(path.startsWith(paths[i])) return 1;

				return 0;
			}

		case UA_LOAD_LIBRARY:
		case UA_POWERBOX:
			return 1;

		default:
			throw Exception(QString("Unhandled policy request type %1").arg(req));
	}
}


